GLUI + Linux + redraw Problem?

I am using GLUI for my 3dEditor Sumar ( running on Win32, everything works normal.

After porting it to Linux i found out some strange behaviour of my GLUI_subwindow.
When i register my reshape and idle-callback with glui (as it is documented in Glui-reference), the glui subwindow doesn’t get redrawn after a window-resize or using one of the rollouts amd therefore is garbage. I’ve compared my code to the examples which come with glui (and work allright), and there doesn’t seem to be a difference in the vital functions.
If I register callbacks directly to my app, which is considered to be wrong, the subwindow gets updated on klicking Rollouts, but naturally doesnt care about window-reshapes.

Althought my App itself is singlethreaded, I already thought of some threading-troubles (thread unsafeness of glut/glui??) because I am using STLport which happens to be multithreaded, too.

I also found some rumours about bufferswapping and glui too, could this be an issue?

Any suggestions / help / solutions appreciated